The invention relates to internal combustion engines, in particular, to rotary engines, and may be used in vehicles such as automobiles or airplanes, and in portable power plants.
A rotary piston engine proposed by Wankel comprises a triangular rotor placed inside a cylindrical housing, the profile of which is made in accordance with an epitrochoid. The rotor is mounted so that it may rotate on an eccentric shaft and is rigidly connected to a movable gear wheel which interacts with a stationary gear wheel. The rotor with the movable gear wheel revolves around the stationary wheel so that its edges slide along the inner surface of the housing, cutting off the variable volumes of the chambers of a channel for passing the working medium, which is formed between the inner surface of the housing and the surface of the rotor. The housing is provided with ports for the supply of a fuel mixture and the discharge of exhaust gases and with a chamber connected to the channel, a sparkplug being mounted in the chamber. The engine does not have massive parts executing reciprocal movement, as a result of which the smoothness of the stroke is enhanced, the noise level and vibration reduced during operation.
However, such a construction has drawbacks related to the presence of gear wheels and an eccentric shaft, which reduce the reliability of operation.
A rotary engine is known in which the rotor is positioned axially (see WO 94/04794, IPC F 01 C 1/344, published Mar. 3, 1994). Such an engine has a housing, inside which a disk rotor with blades is secured on an axle of rotation, the blades being mounted in slots made in the peripheral part of the rotor. The housing consists of two massive covers connected to each other. A removable insert is mounted in an annular recess of each cover from the side of the rotor, the insert forming an annular channel for the passage of the working medium, in which the peripheral part of the rotor together with the blades is located. The blades have the form of rectangular plates, the short sides of which, facing the covers, have a radius curvature, and the slots of the rotor have the form of straight slits corresponding to the form of the cross section of the rectangular plates. The annular channel for passage of the working medium has in section a rectangular shape corresponding to the shape of the blades and is divided by the rotor disk into two parts equal in volume. In the direction along the axle of the rotor the channel bends wave-like in accordance with a periodical law, symmetrical relative to the middle section of the rotor, perpendicular to the axis of the rotor. The wave-like curve along which the channel is bent has a trapezoidal shape in development on a plane. The covers are provided with ports for the supply of air and outlet of exhaust gases, and also with a chamber connected to the channel, with a fuel-injection nozzle mounted in the chamber.
Such an engine has axial positioning of the disk rotor and is completely balanced, and therefore more reliable in operation. However, the complex system of stationary seals on the blade results in their nonuniform wear in the process of operation. The seals which are on the curves of a blade wear down significantly more rapidly than on the straight portions, which results in a loss of the air-tightness of the working chambers, and consequently to a drop of the power or even to a breakdown of the engine.
The object at the base of the invention is to enhance the reliability of operation of a rotary engine construction.
The stated object is achieved in that in a rotary axial engine comprising a housing consisting of two interconnected covers, a rotor secured on an axle, mounted between the covers and having guiding slots on a peripheral portion thereof, the slots being oriented in radial planes along the axle of the rotor, and blades mounted in the slots with the possibility for their reciprocal movement in a direction parallel to the axis of the rotor, wherein an annular recess is made on an inner surface of each cover of such a configuration that an annular channel for passage of a working medium is formed when the covers are connected, the annular channel having in a section passing through the axis of the rotor a shape corresponding to the shape of the blade and bending wavelike according to a periodic law symmetrically relative to the middle section of the rotor, perpendicular to the axis thereof, the blades are provided with sealing elements, the peripheral portion of the rotor with mounted blades is placed inside the annular channel, and each cover is provided with ports for the supply of air into the annular channel and for the discharge of exhaust gases, and also with a chamber connected to the annular channel, in which chamber a fuel-injection nozzle is mounted, in accordance with the invention, each blade has the form of a flattened cylinder, on the side surface of which there are two tangential grooves positioned diametrically opposite each other, the guiding slots of the rotor have a form corresponding to a cross section of the blade in a diametrical plane perpendicular to the direction of the tangential grooves. The annular channel is preferably made bending according to a sinusoid.